import java.math.BigInteger;

/**
 * Created by Administrator on 2014/12/15.
 */
public class Problem8 {
    public static void main(String[] args) {
        BigInteger integer = new BigInteger(
                "73167176531330624919225119674426574742355349194934" +
                        "96983520312774506326239578318016984801869478851843" +
                        "85861560789112949495459501737958331952853208805511" +
                        "12540698747158523863050715693290963295227443043557" +
                        "66896648950445244523161731856403098711121722383113" +
                        "62229893423380308135336276614282806444486645238749" +
                        "30358907296290491560440772390713810515859307960866" +
                        "70172427121883998797908792274921901699720888093776" +
                        "65727333001053367881220235421809751254540594752243" +
                        "52584907711670556013604839586446706324415722155397" +
                        "53697817977846174064955149290862569321978468622482" +
                        "83972241375657056057490261407972968652414535100474" +
                        "82166370484403199890008895243450658541227588666881" +
                        "16427171479924442928230863465674813919123162824586" +
                        "17866458359124566529476545682848912883142607690042" +
                        "24219022671055626321111109370544217506941658960408" +
                        "07198403850962455444362981230987879927244284909188" +
                        "84580156166097919133875499200524063689912560717606" +
                        "05886116467109405077541002256983155200055935729725" +
                        "71636269561882670428252483600823257530420752963450");
        BigInteger result = new BigInteger("0");            /*初始化赋值一个无穷小值*/
        String string = integer.toString();
        for (int i = 0; i < string.length() - 13; i++) {
            String substring = string.substring(i, i + 13);
            BigInteger count = new BigInteger("1");
            for (int j = 0; j < substring.length(); j++) {
                count = count.multiply(new BigInteger(substring.substring(j, j + 1)));
            }
            result = count.max(result);                    /*将两者较大的值赋给result*/
        }
        System.out.println(result);
    }
}
